This invention relates to a process for generating alkali utilizing a complexing reaction.
Alkalies are greatly versatile reagents finding utility in a variety of reactions including hydrolysis, polymerization, color reaction, redox reaction, and neutralization reaction. There are many commercially available products having alkalies contained therein, as exemplified by silver photographic developing solution and various detergents.
However, it is undesirable to contain alkalies in daily direct access products and products requiring aging stability because alkalies have a stability problem in that they tend to be neutralized by absorbing carbon dioxide in air and a safety problem in that they exert an adverse influence on the living body as by irritating the skin during their handling. If an alkali generating process which can solve the aforementioned stability and safety problems is established, such a process would find great potential applications as well as the above-indicated applications.
U.S. Pat. No. 3,260,598 discloses an image forming process utilizing the mechanism wherein alkali-releasing agents, a very slightly water-soluble metal hydroxide Z(OH).sub.n and a compound XY are reacted to release hydroxyl ions to increase the pH wherein Z represents a metal atom, X represents a sodium or potassium atom, Y represents a citrate radical, an oxalate radical, a fluorine atom, a ferricyanide radical, a tartrate radical, a sulfite radical, an ethylenedinitrilo tetraacetate radical, a 1,3-diamino-2-propanol tetraacetate radical, a trimethylamine triacetate radical, and other aliphatic nitrogenous polycarboxylate radicals, and n is 2, 3, or 4. This process, however, is less efficient in alkali generation. There is a need for further improvement.